Begonia caryotarum (Begonia sect. Platycentrum), a new species from southeast Yunnan, China

We describe Begonia caryotarum (B. sect. Platycentrum), a new species from southeast Yunnan, China, found in rock crevices at the foot of limestone hills in Caryota obtusa forest at elev. 700–900 m. The new species is most similar to B. hekouensis in having the same vestiture type on the petioles, flower tepal number, placentation structure, and ovary shape and color, but differs mainly in its leaf blade being asymmetric with an acute apex, tepals pinkish- to orangish-red, larger staminate tepals, anther connectives slightly extended, stigma once spiraled. Its conservation status is categorized as Critically Endangered [CR B2ab (ii, iv), C2a(i)].

Allometric equations to estimate the leaf area of Psychotria colorata (Willd. Ex Schult.) Müll.Arg.

Estimating leaf area using non-destructive methods from regression equations has become a more efficient, quick, and accurate way. Thus, this study aimed to propose an equation that significantly estimates the leaf area of Psychotria colorata (Rubiaceae) through linear leaf dimensions. For this purpose, 200 leaves of different shapes were collected, and length (L), width (W), product of length by width (L.W), and real leaf area (LA) of each leaf blade were determined. Then, equations were adjusted for predicting leaf area using simple linear, linear (0.0), quadratic, cubic, power, and exponential regression models. The proposed equation was selected according to the coefficient of determination (R²), Willmott's agreement index (d), Akaike's information criterion (AIC), mean absolute error (MAE), mean squared error (RMSE) and BIAS index. It was noted that the equations adjusted using L.W met the best criteria for estimating leaf area, but the equation LA = 0.59 * L.W from linear regression without intercept was the most suitable. This equation predicts that 59% of leaf area is explained by L.W. Concluding, the leaf area of P. colorata can be estimated using an allometric equation that uses linear leaf blade dimensions.

Anatomical Variations in Leaves of Pisum sativum Grown with Wastewater of Different Industries

An experiment was carried out to evaluate the anatomical variations in leaves of Pisum sativum grown in medium irrigated with different industrial wastewaters. The Sukhrawa drain area was selected for the collection of wastewaters of different industries in district Okara, Punjab, Pakistan. The experiment was comprised of six wastewater treatments, including protein farm wastewater, rice mill wastewater, combined wastewater of hospital and oil mill, paper mill wastewater and municipal wastewater. The results of anatomical variations in the epidermis, vascular bundle, palisade, and mesophyll cells indicated that the apical part, center, and base of leaf blade all showed normal structure and healthy cells when irrigated with rice mill wastewater and paper mill wastewater, while the center of leaf blade also showed good results when irrigated with the municipal wastewater. So, the results indicate that pea plants can be grown with wastewater from the rice mill, paper mill and municipal wastewater. In the future, wastewater from rice mills, paper mills and municipal wastewater should be considered to check for possible anatomical variations in other plants.

Physiological, Biochemical and Transcriptomic Analysis of the Aerial Parts (Leaf-Blade and Petiole) of Asarum sieboldii Responding to Drought Stress

Asarum sieboldii Miq. is a leading economic crop and a traditional medicinal herb in China. Leaf-blade and petiole are the only aerial tissues of A. sieboldii during the vegetative growth, playing a vital role in the accumulation and transportation of biomass energy. They also act as critical indicators of drought in agricultural management, especially for crops having underground stems. During drought, variations in the morphology and gene expression of the leaves and petioles are used to control agricultural irrigation and production. Besides, such stress can also alter the differential gene expression in these tissues. However, little is known about the drought-tolerant character of the aerial parts of A. sieboldii. In this study, we examined the physiological, biochemical and transcriptomic responses to the drought stress in the leaf blades and petioles of A. sieboldii. The molecular mechanism, involving in drought stress response, was elucidated by constructing the cDNA libraries and performing transcriptomic sequencing. Under drought stress, a total of 2,912 and 2,887 unigenes were differentially expressed in the leaf blade and petiole, respectively. The detection of many transcription factors and functional genes demonstrated that multiple regulatory pathways were involved in drought tolerance. In response to drought, the leaf blade and petiole displayed a general physiological character, a higher SOD and POD activity, a higher MDA content and lower chlorophyll content. Three unigenes encoding POD were up-regulated, which can improve POD activity. Essential oil in petiole was extracted. The relative contents of methyleugenol and safrole in essential oil were increased from 0.01% to 0.05%, and 3.89% to 16.97%, respectively, while myristicin slightly reduced from 24.87% to 21.52%. Additionally, an IGS unigene, involved in eugenol biobiosynthesis, was found up-regulated under drought stress, which was predicated to be responsible for the accumulation of methyleugenol and safrole. Simple sequence repeats (SSRs) were characterized in of A. sieboldii, and a total of 5,466 SSRs were identified. Among them, mono-nucleotides were the most abundant repeat units, accounting for 44.09% followed by tri-, tetra-, penta and hexa-nucleotide repeats. Overall, the present work provides a valuable resource for the population genetics studies of A. sieboldii. Besides, it provides much genomic information for the functional dissection of the drought-resistance in A. sieboldii., which will be useful to understand the bio-regulatory mechanisms linked with drought-tolerance to enhance its yield.

Primulina scutellifolia, a new species of Gesneriaceae from southern Vietnam

Primulina scutellifolia is described as a new species from Khanh Hoa Province, southern Central Vietnam. It is distinct in the genus in having scutellate leaves that make it a highly potential ornamental plant. The new species looks like P. annamensis in general shapes, sizes and colours of habit, inflorescence, flower, and leaf but is distinguishable by adaxially glabrous and abaxially strigose leaves with serrate margins, scutellate leaf blade and appressed downwards tomentose petiole, sparsely glandular hairs on apical 1/2 of the gynoecium and trapeziform one-lipped stigma with slightly emarginated apex.

Bulbophyllum karbianglongensis (Orchidaceae, Epidendroideae), a new species from Assam, India

A new epiphytic Bulbophyllum belonging to section Cirrhopetaloides is described from tropical mixed evergreen forests of Karbi Anglong (Assam, India) with coloured photographs and line drawings. It is allied to the Bulbophyllum bicolor, B. venulosum and B. blaoense, but differs in the size and shape of pseudobulbs, the shape of the leaf blade, and flower size. A detailed description with corresponding color photos and information on the habitat is provided.

Overexpression of PvWOX3a in switchgrass promotes stem development and increases plant height

Switchgrass (Panicum virgatum L.) is an important perennial, noninvasive, tall ornamental grass that adds color and texture to gardens and landscapes. Moreover, switchgrass has been considered a forage and bioenergy crop because of its vigorous growth, low-input requirements, and broad geography. Here, we identified PvWOX3a from switchgrass, which encodes a WUSCHEL-related homeobox transcription factor. Transgenic overexpression of PvWOX3a in switchgrass increased stem length, internode diameter, and leaf blade length and width, all of which contributed to a 95% average increase in dry weight biomass compared with control plants. Yeast one-hybrid and transient dual-luciferase assays showed that PvWOX3a can repress the expression of gibberellin 2-oxidase and cytokinin oxidase/dehydrogenase through apparently direct interaction with their promoter sequences. These results suggested that overexpression of PvWOX3a could increase gibberellin and cytokinin levels in transgenic switchgrass plants, which promotes cell division, elongation, and vascular bundle development. We also overexpressed PvWOX3a in a transgenic miR156-overexpressing switchgrass line that characteristically exhibited more tillers, thinner internodes, and narrower leaf blades. Double transgenic switchgrass plants displayed significant increases in internode length and diameter, leaf blade width, and plant height but retained a tiller number comparable to that of plants expressing miR156 alone. Ultimately, the double transgenic switchgrass plants produced 174% more dry-weight biomass and 162% more solubilized sugars on average than control plants. These findings indicated that PvWOX3a is a viable potential genetic target for engineering improved shoot architecture and biomass yield of horticulture, fodder, and biofuel crops.

Impatiens bijieensis (Balsaminaceae), a new species from karst plateau in Guizhou, China

Impatiens bijieensis X.X. Bai & L.Y. Ren, a new species from Northwest Guizhou, China, is here described and illustrated. This new species is distributed discontiguously in Jiulongshan of Dafang County and Dajiucaiping of Hezhang County, both of which belong to Wumeng mountains area, a karst plateau landform. It is morphologically similar to I. lasiophyton J.D. Hooker and I. leptocaulon J.D. Hooker in height, leaf blade shape and flower form, especially resembles I. lasiophyton in pilose plant. However, it differs in its deep purplish-red to rose-red flower, 2-lobed lower sepal apex and cylindrical capsule. A detailed description, color photographs, and a provisional IUCN red list assessment are provided, and its geographical distribution, ecology, and morphological relationship with relevant similar species are discussed.

Relevance of leaf morphology and biometrics: a study with species of Aphelandra R. Br. (Acanthaceae)

Morphological characteristics, as well as biometrics, govern the description of species. However, systematical comparative analyzes of these aspects between taxa are scarce. The aim of the work was to evaluate the relevance of these characteristics in species of Aphelandra. Leaves of A. longiflora, A. harleyi, A. espirito-santensis, A. nitida, A. sinclairiana and A. squarosa were collected and analyzed for morphologic patterns: phyllotaxis, texture, leaf blade form, symmetry, apex, base, margin, venation and coloring pattern; and for biometric parameters: total length, length and width of the leaf blade, length and diameter of the petiole. We calculated mean and standard deviations. Among the relevant morphological patterns are the shape of the blade, apex and base, and the biometric data showed differences. As conclusion, this analysis proposal proves to be an instrument of accuracy and detail for descriptions.